Interfering Gyroid Boxes

Hi everyone.

I guess this question is quite difficult and requires some advanced mathematical knowledge.

What I have below is two gyroid boxes, each with a different density. (I did not make the Millipede script, I have found it on the forum.)

My question is, how could I make the two boxes flow into each other, in order to make them work structurally as one piece and to be able to perform a structural analysis on the obtained gyroid 'beam'.

Could anyone help me out please? Thanks.